Ask AbFitt...Body effects

It can take time for changes from eating, supplementing and exercise to show up on your body.


Q. When you take a supplement or you diet, or when you exercise or skip workouts, how long does it take for what you do to show up on your body?

A. There’s no absolute answer as to how soon you can see changes in your body from how you eat or from exercise. That’s because so many factors are involved, and it also depends on how you are gauging a change.

Monitoring weight loss on a scale

If you eat an entire watermelon and step on the scale later that day, it may look as if you’ve gained 5 pounds. In reality, you haven’t gained fat, since a watermelon doesn’t have many calories. The scale increase is a reflection of the extra water and fiber you’ve consumed, not fat gain. (And that water and fiber will pass right through you, which is why consuming lots of fruits and vegetables ultimately helps you lose body fat.)

Conversely, if you go on a three-hour bike ride and step on the scale at the end of the day and find yourself 3 pounds lighter, that’s a water-weight loss, not 3 pounds of fat that you’ve burned off during the ride. Your ride may have burned about 450 calories per hour, or around 1,350 calories, which is the equivalent of less than a half-pound of body fat. The extra weight is simply water loss from sweating and depleting some of your glycogen, or stored carbohydrates in your muscles. If you went on long rides every day for a month, you’d see more permanent fat loss, since the calorie burn from every ride would add up

Diets where you follow a very low-calorie diet, or eliminate or drastically cut down on carbs, lead to extra water loss. It may appear as if you’ve lost 5 or more pounds in a week, but that’s mostly water weight, not pure fat loss. (I’ve written more about water-weight loss here.)

For these and other reasons, judging by scale weight can be tricky, and it’s better to look at weight ranges over time. Your body may fluctuate a few pounds in both directions daily due to food and liquid intake and exercise, but if the general range drops over time, you’ll know that you’ve lost a few pounds of fat as well.

The general recommendation is that one-half to 2 pounds of body weight lost per week from dieting or from dieting and exercise is a safe and achievable amount. Weight loss (or fat loss) from exercise alone may hover at the lower end of this range, or it might be even slower. And it all depends on how many calories you burn over the week.

The key thing to remember is that it takes time to see measurable differences in fat loss, especially when you exercise. But if you are doing regular cardio workouts, fat loss is happening even when it’s not immediately evident in terms of inches lost. Be patient and stick to your healthful eating and exercise plan. Over time, you will notice a difference. (I’ve written more about that here.)

Gaining fat or muscle

Gaining pounds of fat or muscle is also not so immediate. If you ate an entire chocolate cake in one day beyond your normal food intake, you are unlikely to pack on 5 pounds of body fat in one day. Typically, the body self-regulates, leading you to eat dramatically less the following day. Over a week, your calorie intake may end up being fairly balanced and your weight may stay stable, or you may gain less than you would expect from one or two days of overeating.

Of course, different people have different abilities to absorb and burn the foods they eat and to self-regulate after overeating. Exercise may be key to managing overeating: There’s evidence that a trained exerciser may be better able to burn, rather than store, excess fat that they eat than a sedentary person.

Building muscle takes time. Some people attribute weight gain after starting an exercise program, or their failure to lose weight, to the fact that they are building muscle. This is probably not the case for most. Here’s why:

In the initial few weeks of a resistance-training program, you can get measurably stronger, but you will not hypertrophy, or gain more muscle, until weeks or months later. And even then, it takes eating more calories than you burn off each day and lifting very heavy weights (not just 5-pound dumbbells) to trigger the anabolic muscle-building process. (That’s why body builders spend hours in the gym and often supplement with extra calories in the form of bars or shakes.)

Body changes from exercise

Most exercise and weight loss studies have participants follow a program for at least 10 or 12 weeks to be able to detect body fat, strength, power, weight or other differences from a plan. The longer one follows a program, whether it’s a diet or exercise plan, the greater those changes will be.

We live in a culture of quick fixes, but when it comes to the body, quick fixes are rarely possible and almost never permanent. So, rather than ask yourself, “How fast?” train yourself to envision how long you will be able to enjoy continued improvements in your health and your body shape by living a healthy lifestyle. Learn to love the workout, the results will follow.



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